Ongoing Research Projects at MSU

1. Stretchable electronics for displaying, sensing, and energy harvesting applications

In this project, our group aims to develop a large-area intrinsically stretchable electronic system (Smart Fabrics) comprising monolithically integrated sensor and OLED array, fabricated entirely using a low-cost printing process.
  • All electronic devices made with nanomaterial- or polymer-based elastic electronic materials
  • Extremely lightweight and can be stretched by at least 50% to allow conformable coverage of curved surfaces
  • Capable of displaying information and collecting real-time mapping data of pressure, strain, temperature, light
Such a system is idea for applications in consumer electronics such as stretchable display, wearable electronics for health monitoring, biomedical, and soft robotics areas.

Key publications:
Advanced Materials, in press (2017)
Advanced Electronic Materials, in press (2017)
ACS Nano, Vol. 10, 11459-11468 (2016)
Nanoscale Research Letters, Vol. 10, 320 (2015) (Review Paper)

2. Ink formulation and process development for high-performance printed electronics

We develop various types of electronic inks in-house for scalable fabrication of electronic devices and circuits on both elastic and plastic substrates.

Key publications:
Applied Physics Letters, Vol. 110, 123105 (2017)
ACS Nano, Vol. 10, 11459-11468 (2016)
Advanced Functional Materials, Vol. 25, 5698-5705 (2015)
Nano Letters, Vol. 13, 3864-3869 (2013)
Nano Letters, Vol. 11, 5301-5308 (2011)

3. 2D semiconductor for high-performance nanoelectronics and optoelectronics

Our group studies various types of 2-dimensional semiconductors such as black phosphorous and transition metal dichalcogenides that are atomically-thin. We explore their electronic and optoelectronic applications as high-performance transistors, sensors, photodetectors, IR imagers, and so on.

Key publications:
ACS Applied Materials & Interfaces, Vol. 9, 10019-10026 (2017)
Advanced Electronic Materials, Vol. 2, 1500346 (2016)
ACS Nano, Vol. 9, 9236-9243 (2015)

PhD & Postdoc Research

Roadmap of our early work on carbon nanotube electronics

Two review papers about our early work on carbon nanotube electronics: 
Chemical Society Reviews, Vol. 42, 2592–2609 (2013)
Nanoscale, Vol. 5, 9483–9502 (2013)

I. System-level flexible electronics using inorganic nanomaterials

We demonstrated various types of nanomaterials-based electronic systems including user-interactive electronic skin, full-color AMOLED display, integrated circuits, and ultra-high-speed (ft >100 GHz) transistors on flexible substrates. The goal was to heterogeneously integrate different types of nanomaterials and electronic components for “system-on-plastic” applications. 

Key publications: 
Nature Materials, Vol. 12, 899–904 (2013)
Nano Letters, Vol. 12, 1527–1533 (2012)
Nano Letters, Vol. 12, 4140–4145 (2012)
Nano Letters, Vol. 13, 5425–5430 (2013)

2. Nanomaterials-based radio-frequency electronics 

We developed a self-aligned T-gate platform for fabricating high-performance short channel RF transistors with minimized parasitic capacitance using carbon nanotubes, graphene, and 2D III-V nanomembranes. 

Key publications:
Nano Letters, Vol. 12, 4140–4145 (2012) 
Nano Letters, Vol. 12, 1527–1533 (2012) 
ACS Nano, Vol. 5, 4169–4176 (2011)
ACS Nano, Vol. 6, 3371–3376 (2012) 
ACS Nano, Vol. 6, 6936–6943 (2012) 

3. Solution-processed semiconducting carbon nanotube network for macroelectronics 

We were the first to report a highly-scalable, low-cost, and solution-based platform for wafer-scale deposition of high purity semiconducting carbo nanotube thin film. This material platform was subsequently used in numerous device applications including both p-type and n-type thin-film transistors, CMOS integrated circuits, RF electronics, display electronics, transparent electronics, flexible electronics, and printed electronics. 

Key publications:
Nano Letters, Vol. 9, 4285–4291 (2009)
Nano Letters, Vol. 11, 4852–4858 (2011)
Nano Letters, Vol. 11, 5301–5308 (2011)
Nano Letters, Vol. 12, 1527–1533 (2012)
ACS Nano, Vol. 4, 7123–7132 (2010)
ACS Nano, Vol. 5, 3284–3292 (2011)
ACS Nano, Vol. 6, 7412–7419 (2012)

4. Type- and chirality-controlled synthesis of carbon nanotubes 

CVD growth of aligned carbon nanotubes with well-defined electronic type (metallic vs. semiconducting) and chirality was achieved.

Key publications:
Nature Communications, Vol. 3, 1199 (2012)
ACS Nano, Vol. 6, 7454–7462 (2012)

5. Horizontally aligned carbon nanotubes for nanoelectronic applications 

In this project, we demonstrated wafer-scale CVD growth and transfer of high density aligned carbon nanotubes for high-performance field-effect transistors and CMOS integrated circuits.

Key publications:
Nano Letters, Vol. 9, 189–197 (2009)
ACS Nano, Vol. 5, 1147–1153 (2011)
Nano Research, Vol. 3, 831–842 (2010)
Applied Physics Letters, Vol. 93, 033101 (2008)